ptolemy.actor.lib.jni
Class PointerToken

java.lang.Object
  ptolemy.data.Token
      ptolemy.actor.lib.jni.PointerToken

All Implemented Interfaces:

java.io.Serializable

public class PointerToken
extends Token

A token that contains the memory location of a C object. Used to maintain C objects between JNI calls. Attempts to access the object from Java will raise an IllegalActionException.

Note that this class assumes a 32-bit memory size so that an pointer may be held in an integer. Actors that use this class are not likely to work on a 64-bit machine, see Bug 285 - Codegen PointerTokens do not work on 64 bit Java because PointerToken assumes 32 bits

Since:

Ptolemy II 7.1

Version:

$Id: PointerToken.java 57046 2010-01-27 23:35:53Z cxh $

Author:

Teale Fristoe

See Also:

Serialized Form

Accepted Rating:

Red

Proposed Rating:

Red (tbf)

Nested Class Summary

static class

PointerToken.PointerType The pointer type.

Field Summary

private static boolean	_checked32Bit True if we have checked that we are on a 32 Bit platform.
private static boolean	_is32Bit True if we are on a 32Bit platform.
private int	_value The memory address of the pointer.
static Type	POINTER The Pointer type: the least upper bound of all the pointer types.

Fields inherited from class ptolemy.data.Token

NIL

Constructor Summary

PointerToken()
Construct an empty token.

PointerToken(int pointer)
Construct a token with the specified memory location.

Method Summary

private static void	_check32Bit()
Type	getType() Return the type of this token.
int	getValue() Return the address of the pointer.
static boolean	is32Bit() Return true if this is a 32bit JVM.
BooleanToken	isEqualTo(Token rightArgument) Test for equality of the values of this Token and the argument Token.
java.lang.String	toString() Return a String representation of the PointerToken, including the address.

Methods inherited from class ptolemy.data.Token

add, addReverse, divide, divideReverse, isCloseTo, isCloseTo, isNil, modulo, moduloReverse, multiply, multiplyReverse, notSupportedConversionMessage, notSupportedIncomparableConversionMessage, notSupportedIncomparableMessage, notSupportedMessage, notSupportedNullNilStringMessage, one, pow, subtract, subtractReverse, zero, zeroReturnType

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

POINTER

public static final Type POINTER

The Pointer type: the least upper bound of all the pointer types.

_checked32Bit

private static boolean _checked32Bit

True if we have checked that we are on a 32 Bit platform.

_is32Bit

private static boolean _is32Bit

True if we are on a 32Bit platform.

_value

private int _value

The memory address of the pointer.

Constructor Detail

PointerToken

public PointerToken()

Construct an empty token.

PointerToken

public PointerToken(int pointer)
             throws IllegalActionException

Construct a token with the specified memory location.

Parameters:

pointer - The specified object referred to by this token.

Throws:

IllegalActionException - If the argument is not of the appropriate type (may be thrown by derived classes, but is not thrown here).

Method Detail

getType

public Type getType()

Return the type of this token.

Overrides:

getType in class Token

Returns:

POINTER, the least upper bound of all the pointer types.

getValue

public int getValue()

Return the address of the pointer.

Returns:

The int that this Token was created with.

isEqualTo

public final BooleanToken isEqualTo(Token rightArgument)
                             throws IllegalActionException

Test for equality of the values of this Token and the argument Token. Two PointerTokens are equal if their addresses are equal.

Overrides:

isEqualTo in class Token

Parameters:

rightArgument - The Token to test against.

Returns:

A boolean token that contains the value true if the addresses are the same.

Throws:

IllegalActionException - Not thrown in this base class.

toString

public java.lang.String toString()

Return a String representation of the PointerToken, including the address.

Overrides:

toString in class Token

Returns:

A String representation of the PointerToken.

is32Bit

public static boolean is32Bit()

Return true if this is a 32bit JVM.

Returns:

true if this is a 32bit JVM.

_check32Bit

private static void _check32Bit()